Effects of cyromazine and abamectin on the leafminer, Liriomyza huidobrensis and its parasitoid, Diglyphus isaea in celery

Field trials were conducted for 2 yr on celery (Apium graveolens L.) to determine the effects of two translaminar insecticides (abamectin and cyromazine) on the agromyzid leafminer, Liriomyza huidobrensis (Blanchard), and the eulophid parasitoid, Diglyphus isaea Walker. Abamectin and cyromazine were applied once early in the growing season by spray or drip application. Yellow sticky traps and leaf samples were used to monitor population levels; a gas chromatograph-mass spectrometer was used to monitor cyromazine residues within the celery plants during 1 yr. Spray applications of abamectin and cyromazine significantly reduced larval leafminers and D. isaea. Contrary to grower practices, application of cyromazine by drip irrigation systems had minor effects on larval leafminer and D. isaea as compared to spray application. Cyromazine residues in the plants treated by spray application declined sharply after 1 wk, and no residues were detected 2 wk after application; less than 0.05 ppm cyromazine residues were detected in plants treated by drip application. Implications of these results on management practices are discussed.     

几种杀虫剂对南美斑潜蝇及其寄生蜂潜蝇茧蜂的毒力

测定了阿维菌素、灭蝇胺、杀虫单、毒死蜱、灭多威、顺式氯氰菊酯6种杀虫剂对南美斑潜蝇2龄幼虫、成虫及其寄生蜂潜蝇茧蜂的室内毒力,并考察了灭蝇胺、阿维菌素和杀虫单对南美斑潜蝇的田间防效。在所研究浓度下,阿维菌素、灭蝇胺对2龄幼虫的毒力较高,但对南美斑潜蝇成虫和潜蝇茧蜂的毒力较低;杀虫单对南美斑潜蝇成虫、2龄幼虫和潜蝇茧蜂的毒力均较高;毒死蜱、灭多威、顺式氯氰菊酯对南美斑潜蝇2龄幼虫的毒力较低,而对潜蝇茧蜂的毒力较高。田间条件下,灭蝇胺、阿维菌素和杀虫单都对田间南美斑潜蝇具有较高防效。     

Biological control of the leafminer,Liriomyza trifolii by introduction,releasing, evaluation of the parasitoids Diglyphus isaea and Dacnusa sibirica on vegetables crops in greenhouses in Egypt

Abstract

The serpentine leafminer, Liriomyza trifolii (Burgess) (Diptera: Agromyzidae), is one of the most serious pests of various floricultural and vegetable crops. The European strains of the parasitoids Diglyphus isaea (Walker) (Hymenoptera: Eulophidae) and Dacnusa sibirica Telenga (Hymenoptera: Braconidae) were imported from The Netherlands. A total of 90,000 of these parasitoids were reared and released on cucumber and tomato in greenhouses. The parasitism rates of D. sibirica reached maximum 11.6% and 7.2% in the 11th week from the releasing date, on cucumber and tomato, respectively. Also the parasitism rates of the European strain of D. isaea increased until it reached a maximum 2.1% and 1.4%, in the tenth week from the releasing date on cucumber and tomato, respectively. It is concluded that the parasitoids D. sibirica and the European strain of D. isaea can be established in Egypt.     

Contrasting patterns of ovarian development and oogenesis in two sympatric host-feeding parasitoids,Diglyphus isaea and Neochrysocharis formosa (Hymenoptera: Eulophidae)

Diglyphus isaea (Walker) and Neochrysocharis formosa (Westwood) (Hymenoptera: Eulophidae) are common idiobiont parasitoids of leafminers attacking vegetable crops. They exhibit differing levels of synovigeny, and host feeding enhances their fecundity and longevity. The reproductive systems of these two parasitoids are typical of hymenopteran eulophids, consisting of two ovaries, each usually comprising three polytrophic meroistic ovarioles. Diglyphus isaea possesses two obvious oviduct accessory glands, which are absent in N. formosa. Both parasitoids underwent oosorption when starved, while feeding on host larvae promoted oogenesis and egg maturation. In both, oogenesis and vitellogenesis commenced on the first day of the pupal stage rather than after eclosion. Formation of ovarioles in D. isaea commenced 1 day earlier than in N. formosa. Mature eggs were rarely observed in ovaries of newly emerged D. isaea, but usually a few were present in N. formosa. When hosts (second–third instar Liriomyza sativae larvae) were provided, the number of mature eggs in D. isaea ovaries initially increased and then stabilized, while in N. formosa, the number first increased and then decreased. Diglyphus isaea had fewer but larger eggs than N. formosa did. Thus, synovigenic divergence begins at the pupal stage and may result in different life-history traits of adults.     

入侵害虫南美斑潜蝇在西藏首次发现及其寄生蜂调查

【目的】南美斑潜蝇Liriomyza huidobrensis为我国重要的入侵害虫,我们于2017年7月首次发现其已扩散至西藏。本研究旨在了解西藏地区南美斑潜蝇的发生现状及其寄生蜂种类。【方法】2017和2018年6月上旬-9月中旬对西藏拉萨、林芝、山南和日喀则4个地区的南美斑潜蝇的发生危害及其寄生蜂组成进行了调查采样。【结果】调查的西藏这4个地区均发现南美斑潜蝇分布和危害;温室发生时间为6月上旬-9月中旬,而露地的发生高峰在7月下旬-8月上旬。其寄主植物有9科21种,主要有豆科(Fabaceae)、茄科(Solanaceae)和伞形科(Umbelliferae)等,主要嗜好经济作物有豇豆Vigna unguiculata, 扁豆Lablab purpureus , 莴笋Lactuca sativa var. angustana和白菜Brassica rapa ssp. pekinensis。其寄生蜂包括姬小蜂科(Eulophidae)、茧蜂科(Braconidae)和瘿蜂科(Cynipidae)共计3科9属16种,分别为双斑潜蝇姬小蜂Diglyphus bimaculatus, 豌豆潜蝇姬小蜂Diglyphus isaea, 小斑潜蝇姬小蜂Diglyphus minoeus, 万氏潜蝇姬小蜂Diglyphus wani, Diglyphus sp., 纵纹瑟姬小蜂Cirrospilus vittatus, Hemiptarsenus sp., 芙新姬小蜂Neochrysocharis formosa, 底比斯姬小蜂Chrysocharis pentheus, 普金姬小蜂Chrysocharis pubicornis, Chrysocharis sp., 潜蝇柄腹姬小蜂Pediobius metallicus, Pnigalio sp., 西伯利亚离颚茧蜂Dacnusa sibirica, Dacnusa sp.和Gronotoma sp.;其中优势种为西伯利亚离颚茧蜂、双斑潜蝇姬小蜂和豌豆潜蝇姬小蜂,其个体数量占比分别为总采集个体数的48.7%, 22.1%和12.9%。【结论】西藏南美斑潜蝇的寄生蜂种类丰富,发挥着重要的自然控制作用。建议进一步加强优势寄生蜂生物学、控害潜力评价以及利用研究,为南美斑潜蝇的绿色防控提供指导。     

Using hosts of mixed sizes to reduce male-biased sex ratio in the parasitoid wasp, Diglyphus isaea

Overproduction of males in mass rearing of parasitic Hymenoptera contributes to higher costs for biological control because only females directly kill pests. We present a technique, based on manipulating host composition, to generate less male‐biased sex ratios in parasitoid species that adjust their sex allocation in response to relative host size. Our system consisted of chrysanthemum, Dendranthema grandiflora Tzvelev var. ‘Miramar’; a leafminer, Liriomyza langei Frick (Diptera: Agromyzidae); and a commercially available parasitoid, Diglyphus isaea (Walker) (Hymenoptera: Eulophidae). We compared the offspring sex ratios of D. isaea females presented with different compositions of L. langei larvae on chrysanthemum. Presenting individual females with only large hosts increased mean sex ratio from 32 to 67% male over 2 days. However, presenting individual females with progressively larger hosts over 1 or 2 days reduced mean sex ratio from 90 to 100% male to less than 30% male. Groups of females produced sex ratios around 58% male if presented with both plants infested by only small hosts and plants infested by only large hosts. In comparison, groups of females produced sex ratios around 48% male if presented with plants infested by both small hosts and large hosts. We compared the use of both small hosts and large hosts to only large hosts for simulated mass rearing of wasps over 8 weeks. Using both small hosts and large hosts produced similar numbers of wasps as using only large hosts, but reduced mean sex ratio of weekly cohorts from 66% male to 56% male. The two techniques produced females of similar size, but using both large hosts and small hosts produced slightly smaller males than using only large hosts. The use of both small hosts and large hosts for mass rearing of D. isaea could reduce actual costs of females by 23%.     

广东肇庆柑橘木虱田间种群对常用药剂的抗药性

室内采用浸叶法测定了柑橘木虱Diaphorina citri敏感种群与田间种群对广东常用药剂的敏感性,明确了柑橘木虱田间种群对阿维菌素、高效氯氰菊酯、吡虫啉、噻虫嗪、啶虫脒和甲维盐6种药剂的抗药性.柑橘木虱田间种群对70％吡虫啉水分散粒剂、20％啶虫脒可溶液剂、3％甲维盐微乳剂处于低水平抗药性,LC50抗性倍数分别为5...     

Lifetime gains and patterns of accumulation and mobilization of nutrients in females of the synovigenic parasitoid, Diglyphus isaea Walker (Hymenoptera: Eulophidae), as a function of diet

In nature, adult parasitoids feed to obtain and use nutrients for supplementing and/or replenishing some of their existing array of nutrient reserves. When adults feed on host or non-host food, they can enhance fitness, typically by increasing egg production or longevity. In the present study, ovigeny index (OI) and impact of female fitness, as well as physiological state on the reproductive strategies, were investigated in the synovigenic parasitoid, Diglyphus isaea, fed on host food (2-3rd instars of Liriomyza sativae larvae), non-host foods (10% honey solution) and starved (distilled water, control). The results showed that D. isaea was a strongly synovigenic parasitoid, of which OI value was 0.002. Both types of food enhanced the fecundity and prolonged the longevity of the females. D. isaea females fed on non-host food showed higher levels of gut sugar, body sugar and glycogen than those fed on host food, but the levels of lipid were higher in the host-fed females. D. isaea females seemed to show lipogenesis, with low rates of lipid catabolism sufficient to satisfy the requirement of egg maturation. Females might absorb lipids directly from the haemolymph of paralyzed hosts.     

水稻害虫化学生态调控研究进展

自然界中,在昆虫和植物种内与种间都存在着复杂的化学联系。开发利用生态系统中这些调控生物种内种间关系的生态功能分子,可望有效降低害虫的种群密度,从而减少化学农药的使用。本文根据目前国内外在利用生态功能分子调控水稻害虫方面的最新研究成果,分别就利用昆虫性信息素、水稻挥发物、非寄主植物提取物、化学激发子以及遗传改良水稻品种等在调控水稻害虫及其天敌中作用的研究进展进行了综述,并提出了今后的研究重点与方向。希望通过本文能促进化学生态调控技术在水稻害虫治理中的应用,以减轻水稻害虫治理对化学农药的依赖。     

Responses of the three-toed sloth, Bradypus tridactylus, to some commonly used pharmacologic agents. II. Chloralose and reserpine

1. Chloralose, 50 mg/kg i.v., is a safe effective anesthetic for sloths and reduces incidence of cardiac arrhythmias. 2. However, chloralose blocks baroreflexes and may reduce the sensitivity of beta 1 cardiac receptors. 3. Reserpine, 0.70 mg/kg given i.v. in divided doses, blocks the hypertensive effect of 100 micrograms/kg of tyramine in sloths. 4. Reserpine in this dosage materially reduces arterial pressure and heart rate; these effects last at least 7 days. 5. Reserpine potentiates the hypertensive effects of epinephrine and norepinephrine materially. 6. In sloths reserpine increases cardiac irritability but does not block baroreflexes. 7. As is true with most other drugs sloths are more sensitive to chloralose and reserpine than most common laboratory animals.     

Molecular and phylogenetic characterization of Ostreopsis (Dinophyceae) and the description of a new species,Ostreopsis rhodesae sp. nov., from a subtropical Australian lagoon

Cryptic and pseudo-cryptic species are common amongst marine phytoplankton, and may cause misleading inferences of ecological and physiological data of plankton community studies. Deciphering the diversity and distribution of species of the benthic dinoflagellate Ostreopsis is one example, as there are many morphologically indistinct clades that differ greatly genetically and toxicologically from one another. In this study, a new species, Ostreopsis rhodesae from the southern Great Barrier Reef was described. While it initially appeared to be highly similar to several other Ostreopsis species, we found O. rhodesae can be distinguished based on the relative size of the second apical plate (2′), which is twice as long as the APC plate, and separates the third apical (3′) from the third precingular (3′′) plate. Phylogenetic trees based on the SSU, ITS/5.8S and D1-D2 and D8-D10 regions of the LSU rRNA were well supported, and showed a clear difference to other Ostreopsis clades. Compensatory base changes (CBCs) were identified in helices of the ITS2 between O. rhodesae and O. cf. ovata and O. cf. siamensis, which were also present in the same habitat. Fish gill cell lines were toxic to O. rhodesae, cell extracts but no palytoxin-like analogues were found in them. The findings highlight a case of pseudo-cryptic speciation, found in sympatry with closely related and morphologically similar species, but biologically and functionally distinct.     

Correction to: Microcella flavibacter sp. nov., isolated from marine sediment,and reclassification of Chryseoglobus frigidaquae,Chryseoglobus indicus,and Yonghaparkia alkaliphila as Microcella frigidaquae comb. nov., Microcella indica nom. nov., and Microcella alkalica nom. nov

Antonie van Leeuwenhoek - In the original publication of the article, the protologue for Microcella indica was incorrectly published as “nom. nov.”. The correct name is Microcella...     

Problems in the application of gel filtration to the desalting of organic compounds: retardation of aromatic and heteroaromatic anions by commonly used salts.

On Bio-Gel P-2 columns, certain inorganic salts elute considerably later than nucleotides and other anionic compounds of similar molecular weight when they are run separately. This would suggest that such compounds should be readily desalted by gel filtration. With some salts (e.g., NaCl, KI, KSCN) this is indeed the case. With others, however(K₂HPO₄, CH₃COONa, HCOONH₄), there is complete overlap between the peaks of the salt and the organic compound. Studies with different organic compounds and salts suggest that this entrapment within the salt peak may be due to opposing electrostatic and hydrophobic influences on the mobility of organic anions.     

Description of three new Alteromonas species Alteromonas antoniana sp. nov., Alteromonas lipotrueae sp. nov. and Alteromonas lipotrueiana sp. nov. isolated from marine environments,and proposal for reclassification of the genus Salinimonas as Alteromonas

In the course of a bioprospective study of marine prokaryotes for cosmetic purposes, four strains, MD_567^T, MD_652^T, MD_674 and PS_109^T, were isolated that 16S rRNA gene affiliation indicated could represent three new species within the family Alteromonadaceae. A thorough phylogenetic, genomic and phenotypic taxonomic study confirmed that the isolates could be classified as three new taxa for which we propose the names Alteromonas antoniana sp. nov., Alteromonas lipotrueae sp. nov. and Alteromonas lipotrueiana sp. nov. In addition, the consistent monophyletic nature of the members of the genera Alteromonas and Salinimonas showed that both taxa should be unified, and therefore we also propose the reclassification of the genus Salinimonas within Alteromonas, as well as new combinations for the species of the former. As the specific epithets profundi and sediminis are already used for Alteromonas species, we created the nomina nova “Alteromonas alteriprofundi” nom. nov. and Alteromonas alterisediminis nom. nov. to accommodate the new names for “Salinimonas profundi” and Salinimonas sediminis. Whole genome comparisons also allowed us to detect the unexpected codification of aromatic hydrocarbon biodegradative compounds, such as benzoate and catechol, whose activity was then demonstrated phenotypically. Finally, the high genomic identity between the type strains of Alteromonas stellipolaris and Alteromonas addita indicated that the latter is a junior heterotypic synonym of Alteromonas stellipolaris.     

Microsatellites and allozymes as the genetic memory of habitat fragmentation and defragmentation in populations of the ground beetle Carabus auronitens (Col., Carabidae)

Aim This paper has three aims: (1) to reconstruct the population history of a flightless silvicolous (forest) ground beetle in a region where strong anthropogenic activity has altered the connectivity of the landscape; (2) to estimate the effects of both contemporary and historical landscape structure on the genetics of populations; and (3) to investigate the reasons for clinal variation in one gene locus found in an earlier study carried out in the same geographical location. Location Münster (Westphalia), north‐west Germany. Methods We investigated 26 populations of the ground beetle Carabus auronitens Fabricius, 1792 by analysing seven polymorphic microsatellite loci and an allozyme locus. Samples of at least 16 individuals per site were studied. These were obtained from dry pitfall traps placed at 23 sites and from three additional (refuge) populations. We used regression and correlation analyses to investigate the effects of both historical and contemporary landscape structure on the allele frequency distributions of the investigated loci. Spatial autocorrelation analysis was used to study possible clinal variations, and admixture rates were calculated in order to assess the genetic influence of populations from possible refuges. Possible reasons for the development of the cline were examined using simulation models. Results The allele frequency distributions at the investigated loci could not be explained by selection or isolation by distance. We found clinal variation in 50% of the investigated loci and our simulations indicated that this was unlikely to have developed by chance. Admixture rates show significant influences of the investigated refuge populations on the populations under study. Main conclusions The findings strongly suggest that the clinal variation is secondary. It results from recolonization of the area by C. auronitens from multiple refuges after anthropogenic landscape changes caused forest fragmentation and led to species isolation.     

Molecular and phenotypic characterization of strains nodulating Anthyllis vulneraria in mine tailings, and proposal of Aminobacter anthyllidis sp. nov., the first definition of Aminobacter as legume-nodulating bacteria

Bacterial strains from Zn-Pb mine tailings were isolated by trapping with Anthyllis vulneraria, a legume-host suitable for mine substratum phytostabilisation. Sequence analysis of the 16S rRNA gene and three housekeeping genes (atpD, dnaK and recA) showed that they were related to those of the genus Aminobacter. DNA-DNA relatedness of representative isolates supported the placement of novel strains in Aminobacter as a new species. Phenotypic data emphasize their differentiation from the other related species of Aminobacter and Mesorhizobium. Aminobacter isolates exhibited nodA sequences tightly related with M. loti as the closest nodA relative. By contrast, their nodA sequences were highly divergent from those of M. metallidurans, another species associated with A. vulneraria that carries two complete copies of nodA. Therefore, the novel bacterial strains efficient on A. vulneraria represented the first occurrence of legume symbionts in the genus Aminobacter. They represent a new species for which the name Aminobacter anthyllidis sp. nov. is proposed (type strain STM4645(T)=LMG26462(T)=CFBP7437(T)).